The present invention relates to an enclosed switchboard.
Prior art enclosed switchboards used in a control center are shown in FIGS. 1 and 2. As shown in FIGS. 1 and 2, a plurality of enclosed switchboards 2 are disposed side by side, each comprising a plurality of stacked unit devices 1, for example. A vertical housing 6 forming the external case of each switchboard 2 comprises side plates 3, a back plate 4 and a front panel 5.
Various electrical devices and supporters thereof have to be mounted in the vertical housing 6. Mounting them directly onto the flat side plates 3 is difficult and does not provide sufficient mechanical strength, so that support plates 12 as shown in FIG. 3 are provided inside of the side plates 3. As illustrated in FIG. 1, a pair of support plates 12 are disposed on one of the side plates 3, adjacent to each other, and another pair of support plates 12 are disposed on the other side plate 3, adjacent to each other, to confront to the first-mentioned pair of support plates 3. The support plates 12 confronting each other are connected to each other by a connecting strip 51, with the bent ends 51a of the strip 51 being secured to the support plates 3 by means of bolts not shown. These support plates are used to support and insulate a vertical bus-bar, not shown, extending through the center of the vertical housing 6. The support plates 12 are also used for supporting shelves for the unit devices 1.
Each switchboard 2 is enclosed and is separated by the side plate 3 from the adjacent unit switchboard 2. As a result, no ventilation occurs between adjacent unit switchboards 2, and accordingly the switchboard 2 in the middle suffers a greater temperature rise. Also, it is difficult to provide wirings interconnecting the unit devices 1 in the adjacent switchboards 2. Moreover, the connection between the suppport plate 12 and the connecting strip 51 in a manner as illustrated does not provide sufficient mechanical strength and hence necessitates reinforcement.